// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2010 Gael Guennebaud <gael.guennebaud@inria.fr>
// Copyright (C) 2016 Konstantinos Margaritis <markos@freevec.org>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_COMPLEX32_ALTIVEC_H
#define EIGEN_COMPLEX32_ALTIVEC_H

namespace Eigen {

namespace internal {

#if !defined(__ARCH__) || (defined(__ARCH__) && __ARCH__ >= 12)
    static Packet4ui p4ui_CONJ_XOR = {0x00000000, 0x80000000, 0x00000000, 0x80000000};  //vec_mergeh((Packet4ui)p4i_ZERO, (Packet4ui)p4f_MZERO);
#endif

    static Packet2ul p2ul_CONJ_XOR1 = (Packet2ul)vec_sld((Packet4ui)p2d_ZERO_, (Packet4ui)p2l_ZERO, 8);  //{ 0x8000000000000000, 0x0000000000000000 };
    static Packet2ul p2ul_CONJ_XOR2 = (Packet2ul)vec_sld((Packet4ui)p2l_ZERO, (Packet4ui)p2d_ZERO_, 8);  //{ 0x8000000000000000, 0x0000000000000000 };

    struct Packet1cd
    {
        EIGEN_STRONG_INLINE Packet1cd() {}
        EIGEN_STRONG_INLINE explicit Packet1cd(const Packet2d& a) : v(a) {}
        Packet2d v;
    };

    struct Packet2cf
    {
        EIGEN_STRONG_INLINE Packet2cf() {}
        EIGEN_STRONG_INLINE explicit Packet2cf(const Packet4f& a) : v(a) {}
#if !defined(__ARCH__) || (defined(__ARCH__) && __ARCH__ < 12)
        union
        {
            Packet4f v;
            Packet1cd cd[2];
        };
#else
        Packet4f v;
#endif
    };

    template <> struct packet_traits<std::complex<float>> : default_packet_traits
    {
        typedef Packet2cf type;
        typedef Packet2cf half;
        enum
        {
            Vectorizable = 1,
            AlignedOnScalar = 1,
            size = 2,
            HasHalfPacket = 0,

            HasAdd = 1,
            HasSub = 1,
            HasMul = 1,
            HasDiv = 1,
            HasNegate = 1,
            HasAbs = 0,
            HasAbs2 = 0,
            HasMin = 0,
            HasMax = 0,
            HasBlend = 1,
            HasSetLinear = 0
        };
    };

    template <> struct packet_traits<std::complex<double>> : default_packet_traits
    {
        typedef Packet1cd type;
        typedef Packet1cd half;
        enum
        {
            Vectorizable = 1,
            AlignedOnScalar = 1,
            size = 1,
            HasHalfPacket = 0,

            HasAdd = 1,
            HasSub = 1,
            HasMul = 1,
            HasDiv = 1,
            HasNegate = 1,
            HasAbs = 0,
            HasAbs2 = 0,
            HasMin = 0,
            HasMax = 0,
            HasSetLinear = 0
        };
    };

    template <> struct unpacket_traits<Packet2cf>
    {
        typedef std::complex<float> type;
        enum
        {
            size = 2,
            alignment = Aligned16,
            vectorizable = true,
            masked_load_available = false,
            masked_store_available = false
        };
        typedef Packet2cf half;
    };
    template <> struct unpacket_traits<Packet1cd>
    {
        typedef std::complex<double> type;
        enum
        {
            size = 1,
            alignment = Aligned16,
            vectorizable = true,
            masked_load_available = false,
            masked_store_available = false
        };
        typedef Packet1cd half;
    };

    /* Forward declaration */
    EIGEN_STRONG_INLINE void ptranspose(PacketBlock<Packet2cf, 2>& kernel);

    /* complex<double> first */
    template <> EIGEN_STRONG_INLINE Packet1cd pload<Packet1cd>(const std::complex<double>* from)
    {
        EIGEN_DEBUG_ALIGNED_LOAD return Packet1cd(pload<Packet2d>((const double*)from));
    }
    template <> EIGEN_STRONG_INLINE Packet1cd ploadu<Packet1cd>(const std::complex<double>* from)
    {
        EIGEN_DEBUG_UNALIGNED_LOAD return Packet1cd(ploadu<Packet2d>((const double*)from));
    }
    template <> EIGEN_STRONG_INLINE void pstore<std::complex<double>>(std::complex<double>* to, const Packet1cd& from)
    {
        EIGEN_DEBUG_ALIGNED_STORE pstore((double*)to, from.v);
    }
    template <> EIGEN_STRONG_INLINE void pstoreu<std::complex<double>>(std::complex<double>* to, const Packet1cd& from)
    {
        EIGEN_DEBUG_UNALIGNED_STORE pstoreu((double*)to, from.v);
    }

    template <> EIGEN_STRONG_INLINE Packet1cd pset1<Packet1cd>(const std::complex<double>& from)
    { /* here we really have to use unaligned loads :( */
        return ploadu<Packet1cd>(&from);
    }

    template <> EIGEN_DEVICE_FUNC inline Packet1cd pgather<std::complex<double>, Packet1cd>(const std::complex<double>* from, Index stride EIGEN_UNUSED)
    {
        return pload<Packet1cd>(from);
    }
    template <>
    EIGEN_DEVICE_FUNC inline void pscatter<std::complex<double>, Packet1cd>(std::complex<double>* to, const Packet1cd& from, Index stride EIGEN_UNUSED)
    {
        pstore<std::complex<double>>(to, from);
    }
    template <> EIGEN_STRONG_INLINE Packet1cd padd<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(a.v + b.v); }
    template <> EIGEN_STRONG_INLINE Packet1cd psub<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(a.v - b.v); }
    template <> EIGEN_STRONG_INLINE Packet1cd pnegate(const Packet1cd& a) { return Packet1cd(pnegate(Packet2d(a.v))); }
    template <> EIGEN_STRONG_INLINE Packet1cd pconj(const Packet1cd& a) { return Packet1cd((Packet2d)vec_xor((Packet2d)a.v, (Packet2d)p2ul_CONJ_XOR2)); }
    template <> EIGEN_STRONG_INLINE Packet1cd pmul<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
    {
        Packet2d a_re, a_im, v1, v2;

        // Permute and multiply the real parts of a and b
        a_re = vec_perm(a.v, a.v, p16uc_PSET64_HI);
        // Get the imaginary parts of a
        a_im = vec_perm(a.v, a.v, p16uc_PSET64_LO);
        // multiply a_re * b
        v1 = vec_madd(a_re, b.v, p2d_ZERO);
        // multiply a_im * b and get the conjugate result
        v2 = vec_madd(a_im, b.v, p2d_ZERO);
        v2 = (Packet2d)vec_sld((Packet4ui)v2, (Packet4ui)v2, 8);
        v2 = (Packet2d)vec_xor((Packet2d)v2, (Packet2d)p2ul_CONJ_XOR1);

        return Packet1cd(v1 + v2);
    }
    template <> EIGEN_STRONG_INLINE Packet1cd pand<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(vec_and(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet1cd por<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(vec_or(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet1cd pxor<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(vec_xor(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet1cd pandnot<Packet1cd>(const Packet1cd& a, const Packet1cd& b) { return Packet1cd(vec_and(a.v, vec_nor(b.v, b.v))); }
    template <> EIGEN_STRONG_INLINE Packet1cd ploaddup<Packet1cd>(const std::complex<double>* from) { return pset1<Packet1cd>(*from); }
    template <> EIGEN_STRONG_INLINE Packet1cd pcmp_eq(const Packet1cd& a, const Packet1cd& b)
    {
        Packet2d eq = vec_cmpeq(a.v, b.v);
        Packet2d tmp = {eq[1], eq[0]};
        return (Packet1cd)pand<Packet2d>(eq, tmp);
    }

    template <> EIGEN_STRONG_INLINE void prefetch<std::complex<double>>(const std::complex<double>* addr) { EIGEN_ZVECTOR_PREFETCH(addr); }

    template <> EIGEN_STRONG_INLINE std::complex<double> pfirst<Packet1cd>(const Packet1cd& a)
    {
        std::complex<double> EIGEN_ALIGN16 res;
        pstore<std::complex<double>>(&res, a);

        return res;
    }

    template <> EIGEN_STRONG_INLINE Packet1cd preverse(const Packet1cd& a) { return a; }
    template <> EIGEN_STRONG_INLINE std::complex<double> predux<Packet1cd>(const Packet1cd& a) { return pfirst(a); }
    template <> EIGEN_STRONG_INLINE std::complex<double> predux_mul<Packet1cd>(const Packet1cd& a) { return pfirst(a); }
    EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet1cd, Packet2d)

    template <> EIGEN_STRONG_INLINE Packet1cd pdiv<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
    {
        // TODO optimize it for AltiVec
        Packet1cd res = pmul(a, pconj(b));
        Packet2d s = vec_madd(b.v, b.v, p2d_ZERO_);
        return Packet1cd(pdiv(res.v, s + vec_perm(s, s, p16uc_REVERSE64)));
    }

    EIGEN_STRONG_INLINE Packet1cd pcplxflip /*<Packet1cd>*/ (const Packet1cd& x) { return Packet1cd(preverse(Packet2d(x.v))); }

    EIGEN_STRONG_INLINE void ptranspose(PacketBlock<Packet1cd, 2>& kernel)
    {
        Packet2d tmp = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_HI);
        kernel.packet[1].v = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_LO);
        kernel.packet[0].v = tmp;
    }

    /* complex<float> follows */
    template <> EIGEN_STRONG_INLINE Packet2cf pload<Packet2cf>(const std::complex<float>* from)
    {
        EIGEN_DEBUG_ALIGNED_LOAD return Packet2cf(pload<Packet4f>((const float*)from));
    }
    template <> EIGEN_STRONG_INLINE Packet2cf ploadu<Packet2cf>(const std::complex<float>* from)
    {
        EIGEN_DEBUG_UNALIGNED_LOAD return Packet2cf(ploadu<Packet4f>((const float*)from));
    }
    template <> EIGEN_STRONG_INLINE void pstore<std::complex<float>>(std::complex<float>* to, const Packet2cf& from)
    {
        EIGEN_DEBUG_ALIGNED_STORE pstore((float*)to, from.v);
    }
    template <> EIGEN_STRONG_INLINE void pstoreu<std::complex<float>>(std::complex<float>* to, const Packet2cf& from)
    {
        EIGEN_DEBUG_UNALIGNED_STORE pstoreu((float*)to, from.v);
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> pfirst<Packet2cf>(const Packet2cf& a)
    {
        std::complex<float> EIGEN_ALIGN16 res[2];
        pstore<std::complex<float>>(res, a);

        return res[0];
    }

#if !defined(__ARCH__) || (defined(__ARCH__) && __ARCH__ < 12)
    template <> EIGEN_STRONG_INLINE Packet2cf pset1<Packet2cf>(const std::complex<float>& from)
    {
        Packet2cf res;
        res.cd[0] = Packet1cd(vec_ld2f((const float*)&from));
        res.cd[1] = res.cd[0];
        return res;
    }
#else
    template <> EIGEN_STRONG_INLINE Packet2cf pset1<Packet2cf>(const std::complex<float>& from)
    {
        Packet2cf res;
        if ((std::ptrdiff_t(&from) % 16) == 0)
            res.v = pload<Packet4f>((const float*)&from);
        else
            res.v = ploadu<Packet4f>((const float*)&from);
        res.v = vec_perm(res.v, res.v, p16uc_PSET64_HI);
        return res;
    }
#endif

    template <> EIGEN_DEVICE_FUNC inline Packet2cf pgather<std::complex<float>, Packet2cf>(const std::complex<float>* from, Index stride)
    {
        std::complex<float> EIGEN_ALIGN16 af[2];
        af[0] = from[0 * stride];
        af[1] = from[1 * stride];
        return pload<Packet2cf>(af);
    }
    template <> EIGEN_DEVICE_FUNC inline void pscatter<std::complex<float>, Packet2cf>(std::complex<float>* to, const Packet2cf& from, Index stride)
    {
        std::complex<float> EIGEN_ALIGN16 af[2];
        pstore<std::complex<float>>((std::complex<float>*)af, from);
        to[0 * stride] = af[0];
        to[1 * stride] = af[1];
    }

    template <> EIGEN_STRONG_INLINE Packet2cf padd<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(padd<Packet4f>(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf psub<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(psub<Packet4f>(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf pnegate(const Packet2cf& a) { return Packet2cf(pnegate(Packet4f(a.v))); }

    template <> EIGEN_STRONG_INLINE Packet2cf pand<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(pand<Packet4f>(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf por<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(por<Packet4f>(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf pxor<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(pxor<Packet4f>(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cf pandnot<Packet2cf>(const Packet2cf& a, const Packet2cf& b) { return Packet2cf(pandnot<Packet4f>(a.v, b.v)); }

    template <> EIGEN_STRONG_INLINE Packet2cf ploaddup<Packet2cf>(const std::complex<float>* from) { return pset1<Packet2cf>(*from); }

    template <> EIGEN_STRONG_INLINE void prefetch<std::complex<float>>(const std::complex<float>* addr) { EIGEN_ZVECTOR_PREFETCH(addr); }

#if !defined(__ARCH__) || (defined(__ARCH__) && __ARCH__ < 12)

    template <> EIGEN_STRONG_INLINE Packet2cf pcmp_eq(const Packet2cf& a, const Packet2cf& b)
    {
        Packet4f eq = pcmp_eq<Packet4f>(a.v, b.v);
        Packet2cf res;
        Packet2d tmp1 = {eq.v4f[0][1], eq.v4f[0][0]};
        Packet2d tmp2 = {eq.v4f[1][1], eq.v4f[1][0]};
        res.v.v4f[0] = pand<Packet2d>(eq.v4f[0], tmp1);
        res.v.v4f[1] = pand<Packet2d>(eq.v4f[1], tmp2);
        return res;
    }

    template <> EIGEN_STRONG_INLINE Packet2cf pconj(const Packet2cf& a)
    {
        Packet2cf res;
        res.v.v4f[0] = pconj(Packet1cd(reinterpret_cast<Packet2d>(a.v.v4f[0]))).v;
        res.v.v4f[1] = pconj(Packet1cd(reinterpret_cast<Packet2d>(a.v.v4f[1]))).v;
        return res;
    }

    template <> EIGEN_STRONG_INLINE Packet2cf pmul<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
    {
        Packet2cf res;
        res.v.v4f[0] = pmul(Packet1cd(reinterpret_cast<Packet2d>(a.v.v4f[0])), Packet1cd(reinterpret_cast<Packet2d>(b.v.v4f[0]))).v;
        res.v.v4f[1] = pmul(Packet1cd(reinterpret_cast<Packet2d>(a.v.v4f[1])), Packet1cd(reinterpret_cast<Packet2d>(b.v.v4f[1]))).v;
        return res;
    }

    template <> EIGEN_STRONG_INLINE Packet2cf preverse(const Packet2cf& a)
    {
        Packet2cf res;
        res.cd[0] = a.cd[1];
        res.cd[1] = a.cd[0];
        return res;
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> predux<Packet2cf>(const Packet2cf& a)
    {
        std::complex<float> res;
        Packet1cd b = padd<Packet1cd>(a.cd[0], a.cd[1]);
        vec_st2f(b.v, (float*)&res);
        return res;
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> predux_mul<Packet2cf>(const Packet2cf& a)
    {
        std::complex<float> res;
        Packet1cd b = pmul<Packet1cd>(a.cd[0], a.cd[1]);
        vec_st2f(b.v, (float*)&res);
        return res;
    }

    EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet2cf, Packet4f)

    template <> EIGEN_STRONG_INLINE Packet2cf pdiv<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
    {
        // TODO optimize it for AltiVec
        Packet2cf res;
        res.cd[0] = pdiv<Packet1cd>(a.cd[0], b.cd[0]);
        res.cd[1] = pdiv<Packet1cd>(a.cd[1], b.cd[1]);
        return res;
    }

    EIGEN_STRONG_INLINE Packet2cf pcplxflip /*<Packet2cf>*/ (const Packet2cf& x)
    {
        Packet2cf res;
        res.cd[0] = pcplxflip(x.cd[0]);
        res.cd[1] = pcplxflip(x.cd[1]);
        return res;
    }

    EIGEN_STRONG_INLINE void ptranspose(PacketBlock<Packet2cf, 2>& kernel)
    {
        Packet1cd tmp = kernel.packet[0].cd[1];
        kernel.packet[0].cd[1] = kernel.packet[1].cd[0];
        kernel.packet[1].cd[0] = tmp;
    }

    template <> EIGEN_STRONG_INLINE Packet2cf pblend(const Selector<2>& ifPacket, const Packet2cf& thenPacket, const Packet2cf& elsePacket)
    {
        Packet2cf result;
        const Selector<4> ifPacket4 = {ifPacket.select[0], ifPacket.select[0], ifPacket.select[1], ifPacket.select[1]};
        result.v = pblend<Packet4f>(ifPacket4, thenPacket.v, elsePacket.v);
        return result;
    }
#else
    template <> EIGEN_STRONG_INLINE Packet2cf pcmp_eq(const Packet2cf& a, const Packet2cf& b)
    {
        Packet4f eq = vec_cmpeq(a.v, b.v);
        Packet4f tmp = {eq[1], eq[0], eq[3], eq[2]};
        return (Packet2cf)pand<Packet4f>(eq, tmp);
    }
    template <> EIGEN_STRONG_INLINE Packet2cf pconj(const Packet2cf& a) { return Packet2cf(pxor<Packet4f>(a.v, reinterpret_cast<Packet4f>(p4ui_CONJ_XOR))); }
    template <> EIGEN_STRONG_INLINE Packet2cf pmul<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
    {
        Packet4f a_re, a_im, prod, prod_im;

        // Permute and multiply the real parts of a and b
        a_re = vec_perm(a.v, a.v, p16uc_PSET32_WODD);

        // Get the imaginary parts of a
        a_im = vec_perm(a.v, a.v, p16uc_PSET32_WEVEN);

        // multiply a_im * b and get the conjugate result
        prod_im = a_im * b.v;
        prod_im = pxor<Packet4f>(prod_im, reinterpret_cast<Packet4f>(p4ui_CONJ_XOR));
        // permute back to a proper order
        prod_im = vec_perm(prod_im, prod_im, p16uc_COMPLEX32_REV);

        // multiply a_re * b, add prod_im
        prod = pmadd<Packet4f>(a_re, b.v, prod_im);

        return Packet2cf(prod);
    }

    template <> EIGEN_STRONG_INLINE Packet2cf preverse(const Packet2cf& a)
    {
        Packet4f rev_a;
        rev_a = vec_perm(a.v, a.v, p16uc_COMPLEX32_REV2);
        return Packet2cf(rev_a);
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> predux<Packet2cf>(const Packet2cf& a)
    {
        Packet4f b;
        b = vec_sld(a.v, a.v, 8);
        b = padd<Packet4f>(a.v, b);
        return pfirst<Packet2cf>(Packet2cf(b));
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> predux_mul<Packet2cf>(const Packet2cf& a)
    {
        Packet4f b;
        Packet2cf prod;
        b = vec_sld(a.v, a.v, 8);
        prod = pmul<Packet2cf>(a, Packet2cf(b));

        return pfirst<Packet2cf>(prod);
    }

    EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet2cf, Packet4f)

    template <> EIGEN_STRONG_INLINE Packet2cf pdiv<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
    {
        // TODO optimize it for AltiVec
        Packet2cf res = pmul(a, pconj(b));
        Packet4f s = pmul<Packet4f>(b.v, b.v);
        return Packet2cf(pdiv(res.v, padd<Packet4f>(s, vec_perm(s, s, p16uc_COMPLEX32_REV))));
    }

    template <> EIGEN_STRONG_INLINE Packet2cf pcplxflip<Packet2cf>(const Packet2cf& x) { return Packet2cf(vec_perm(x.v, x.v, p16uc_COMPLEX32_REV)); }

    EIGEN_STRONG_INLINE void ptranspose(PacketBlock<Packet2cf, 2>& kernel)
    {
        Packet4f tmp = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_HI);
        kernel.packet[1].v = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_LO);
        kernel.packet[0].v = tmp;
    }

    template <> EIGEN_STRONG_INLINE Packet2cf pblend(const Selector<2>& ifPacket, const Packet2cf& thenPacket, const Packet2cf& elsePacket)
    {
        Packet2cf result;
        result.v = reinterpret_cast<Packet4f>(pblend<Packet2d>(ifPacket, reinterpret_cast<Packet2d>(thenPacket.v), reinterpret_cast<Packet2d>(elsePacket.v)));
        return result;
    }
#endif

}  // end namespace internal

}  // end namespace Eigen

#endif  // EIGEN_COMPLEX32_ALTIVEC_H
